Abstract

A sensor having an interdigitated gate electrode field effect transistor (IGEFET) coupled to an electron beam evaporated copper phthalocyanine thin film is used to selectively detect parts-per-billion concentration levels of atmosphere contaminants such as nitrogen dioxide (NO2) and diisopropyl methylphosphonate (DIMP). The sensor is excited with a voltage pulse, and its time- and frequency-domain response are examined. The envelopes of the magnitude of the normalized difference frequency spectrums reveal features which unambiguously distinguish the NO2 and DIMP exposures.

Document Type

Patent

Status

Issued

Issue Date

12-10-1991

Patent Number

US 5071770 A [ 5,071,770 ]

CPC Classification

G 01 N 27/4141

Application number

07/608852

Assignees

The United States of America as represented by the Secretary of the Air Force

Filing Date

11-5-1990

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